Python Forum

Hello,

I can't figure out how to change a button's label when clicking on it:

import wx

class MyFrame(wx.Frame):    
    def __init__(self):
        super().__init__(parent=None, title='Hello World')
        panel = wx.Panel(self)        
        my_sizer = wx.BoxSizer(wx.VERTICAL)        

        my_btn = wx.Button(panel, label='Press Me')
        my_btn.Bind(wx.EVT_BUTTON, self.on_press)
        my_sizer.Add(my_btn, 0, wx.ALL | wx.CENTER, 5)        
        panel.SetSizer(my_sizer)        
        self.Show()

    def on_press(self, event):
		#self.SetLabel("New Value")
		#my_btn.SetLabel("blah")
		#self.SetLabel(my_btn,"New Value")
		self.SetLabel(self.my_btn,"New Value")

if __name__ == '__main__':
    app = wx.App()
    frame = MyFrame()
    app.MainLoop()

Do I need some kind of refresh/redraw?

Thank you.

To be able to have a pointer to the button object in the event handler method on_press you need to add self. to the front of my_btn in the __init__ method.
Then you can use the buttons SetLabel method.

import wx


class MyFrame(wx.Frame):
    def __init__(self):
        super().__init__(parent=None, title="Hello World")
        panel = wx.Panel(self)
        my_sizer = wx.BoxSizer(wx.VERTICAL)

        self.my_btn = wx.Button(panel, label="Press Me")
        self.my_btn.Bind(wx.EVT_BUTTON, self.on_press)
        my_sizer.Add(self.my_btn, 0, wx.ALL | wx.CENTER, 5)
        panel.SetSizer(my_sizer)
        self.Show()

    def on_press(self, event):
        self.my_btn.SetLabel("New Value")


if __name__ == "__main__":
    app = wx.App()
    frame = MyFrame()
    app.MainLoop()

    def on_press(self, event):
        #self.SetLabel("New Value")  # Does not work because self is wxFrame, not a button
        #my_btn.SetLabel("blah") # Does not work because my_btn only existed for a brief instant inside MyFrame.__init__()
        #self.SetLabel(my_btn,"New Value")  # Does not work for many reasons.   Is trying to setLabel on a frame to a button
        self.SetLabel(self.my_btn,"New Value") # Does not work because you never assign self.my_btn a value

As Yoriz says, to set the button label, you call SetLabel() for the button.

button = wxButton(parent)
button.SetLabel("Button text goes here")

If you create the button in one method and set the label in another, you need to keep a handle to the button object. The easiest way to do this save the button object in an instance variable.

method make_stuff(self):
    panel = wx.Panel(self)  # Only use panel this one time.  No need to make instance variable
    self.button = wxButton(panel, label="Initial Button Label")  # Will use button later, so make it an instance variable

method change_stuff(self):
    self.button.SetLabel("New Button Label")  # This is the same button created in make_stuff()

Thanks guys. Makes sense.